GE PROPRIETARY INFORMATION 

The information contained in this document is GE proprietary information and is disclosed in confidence. It is the property of GE and shall 

not be used, disclosed to others, or reproduced without the express written consent of GE, including, but without limitation, it is not to be 

used in the creation, manufacture, development, or derivation of any repairs, modifications, spare parts, designs, or configuration 

changes or to obtain regulatory approval to do so. If consent is given for reproduction in whole or in part, this notice and the notice set 

forth on each page of this document shall appear in any such reproduction in whole or in part.

Page: 1 / 9 

Alert Service Bulletin

Approved by Document ID/Revision No.

Issued on

Huck, Steve SB-2016-72-50-00-1/00

21-Jan-2016

This document was approved and issued via the GE Aviation Turboprop Document Workflow Process.

ALERT-SERVICE-BULLETIN-PTDISK-INSPECTION
Page: 2 / 9 

THIS PAGE HAS BEEN INTENTIONALLY LEFT BLANK 
Alert Service Bulletin No./Rev.:

ISSUED REVISED GE Aviation Czech tel.:+420 251 041 111

Beranových 65 fax: +420 257 216 983

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tel.: +420 222 538 111

fax: +420 222 538 222

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Alert Service Bulletin 

GE PROPRIETARY INFORMATION 

The information contained in this document is GE proprietary information and is disclosed in confidence. It is the property of GE and shall 

not be used, disclosed to others, or reproduced without the express written consent of GE, including, but without limitation, it is not to be 

used in the creation, manufacture, development, or derivation of any repairs, modifications, spare parts, designs, or configuration 

changes or to obtain regulatory approval to do so. If consent is given for reproduction in whole or in part, this notice and the notice set 

forth on each page of this document shall appear in any such reproduction in whole or in part.

SUBJECT

The Power Turbine (PT) disc inspection in accordance with M601E Overhaul Manual and M601 engine 

models appropriate Maintenance Manuals. 

This is an Alert Service Bulletin, it is expected that it will be mandated by an Airworthiness Directive. 

1. PLANNING INFORMATION

1.1. Effectivity 

M601 engines with serial numbers listed in appendix A. 

1.2. Compliance 

Engines listed in appendix A. Perform the inspection until the engine reaches PT disc equivalent cycles 

and/or compliance time listed in appendix A. 

1.3. Reason 

Purpose of the Power Turbine disc inspection is identification of the PT disc damage in the area of the 

balancing weights and identification of the PT disc with non conforming geometry of slot radius. The PT 

disc damage could occur during last shop visit or overhaul. The non conformance could occur during 

machining of the PT disc slot. 

1.4. Safety Intent 

Intent of the SB is inspection of potentially damaged PT discs and/or non conforming slot geometry of PT 

disc (if appropriate their replacement) to prevent hazardous effect. 

1.5. Configuration Description 

Configuration of the part does not change. 

SB-2016-72-50-00-1/00
Alert Service Bulletin No./Rev.:

ISSUED REVISED GE Aviation Czech tel.:+420 251 041 111

Beranových 65 fax: +420 257 216 983

199 02 Praha 9 – Letňany

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tel.: +420 222 538 111

fax: +420 222 538 222

PAGE No. REVISION

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1.6. Description 

I. Power Turbine section needs to be removed from the wing, disassembled, inspected (see chap. 

1.12) and assembled in accordance with appendix B. 

II. Inspections 1 & 2 need to be performed by GEAC Customer Support Product Organization (CSPO) 

trained personal. 

III. After inspection, Power Turbine disc balancing plugs must be replaced. Consequently, the Power 

Turbine disc must be rebalanced and reinstalled. This work scope can be performed in an 

authorized service centers only. 

1.7. Approval 

The technical content of this document is approved under the authority of DOA No. EASA.21J.300. 

1.8. Manpower 

7 days 

1.9. Expenses 

GE Aviation covers the cost of return engine shipping to operator (Incoterms 2010 – Delivered at Place 

[DAP]), cost of labor & material required for inspection and repair of Power Turbine disc in repairable 

condition, cost of final engine performance test. 

Operator covers the cost of engine shipping to authorized service center (Incoterms 2010 – Delivered at 

Place [DAP]), cost of replacement Power Turbine disc in case original removed Power Turbine disc is 

considered non-airworthy and/or beyond economical repair. GE Aviation will give 70% concession on 

replacement of Power Turbine disc“. 

1.10. References 

M601E Overhaul Manual 

M601 engine models appropriate Maintenance Manuals 

1.11. Other Publications affected 

None 

1.12. Supplemental Information 

Inspection 1 # PT Disc inspection Instruction of the area below balancing plugs: 

Note – All balancing plugs need to be removed prior to area ‘A’ inspection

Perform Inspection of area ‘A’ (see Picture 1 below):

1. Visual Inspection – perform visual inspection under the good lighting (min 1000 LUX) with the 

magnifying glass (5x magnification) of the disk body - area ‘A’ (see picture below) according to the 

criteria listed in table 1. Pay particular attention to the areas below balancing holes. 

SB-2016-72-50-00-1/00
Alert Service Bulletin No./Rev.:

ISSUED REVISED GE Aviation Czech tel.:+420 251 041 111

Beranových 65 fax: +420 257 216 983

199 02 Praha 9 – Letňany

Czech Republic

tel.: +420 222 538 111

fax: +420 222 538 222

PAGE No. REVISION

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2. FPI Inspection – perform the FPI inspection of the disk body (per GEAC instruction P34.39) - area ‘A’ 

(see Picture 1 below) according to the criteria listed in the table 1. Pay extra attention to the areas below 

balancing holes. 

Picture 1 – Description of the required inspection area 

Table 1 - PT Disc area ‘A’ inspection 1 acceptance criteria 

Description

Power Turbine Disc Part Number

M601-3220.6 M601-3220.5

Witness mark with no 

perceptible depth

Replace, quarantine, repair 

being developed Accept as is

Dot indication

If not deeper than 0.05mm and 

diameter less than 0.1mm

Replace, quarantine, repair 

being developed Accept as is

False drilled dimple

If depth is between 0.05mm to 

0.08mm and diameter more than 

0.1mm

Replace, quarantine, repair 

being developed

Replace, quarantine, 

repair being 

developed

False drilled dimple

Depth is more than 0.08mm

Replace Replace

Linear FPI indication Replace Replace

Pay extra attention in the areas 

below the balancing holes 

Surface Area ‘A’ 

(highlighted in red)

SB-2016-72-50-00-1/00
Alert Service Bulletin No./Rev.:

ISSUED REVISED GE Aviation Czech tel.:+420 251 041 111

Beranových 65 fax: +420 257 216 983

199 02 Praha 9 – Letňany

Czech Republic

tel.: +420 222 538 111

fax: +420 222 538 222

PAGE No. REVISION

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GE PROPRIETARY INFORMATION: Subject to the restrictions on the cover page. Page: 6 / 9 

Inspection 2 # PT Disc inspection Instruction of the PT disc slot area: 

Note – All balancing plugs need to be removed prior to area ‘B’ inspection

Perform Inspection of area ‘B’ (see Picture 2 below):

1) Visual Inspection – perform visual inspection under the good lighting (min 1000 LUX) with the 

magnifying glass (5x magnification) of the disk slot - area ‘B’ (see picture 2 below) according to the 

criteria listed in table 2. Pay particular attention to the areas at radius transition of the slot. 

2) Dimensional Inspection – perform dimensional inspection of the disk slot radii (R1 and R2) and slot 

diameter ‘diam_A’ (see picture 3 below) located in area ‘B’ (see picture 2 below) according to the 

criteria listed in table 2. Dimensional inspection of the R1, R2 and ‘diam_A’ to be performed at 4 

equally spaced places around the slot circumference (measurement to be taken every 90 deg) 

3) FPI Inspection – perform the FPI inspection of the disk slot (per GEAC instruction P34.39) - area ‘B’ 

(see picture 2 below) according to the criteria listed in table 2. Pay extra attention to the areas at 

radius transition of the slot 

SB-2016-72-50-00-1/00
Alert Service Bulletin No./Rev.:

ISSUED REVISED GE Aviation Czech tel.:+420 251 041 111

Beranových 65 fax: +420 257 216 983

199 02 Praha 9 – Letňany

Czech Republic

tel.: +420 222 538 111

fax: +420 222 538 222

PAGE No. REVISION

01 21 2016 - - - 7 of 9 -

GE PROPRIETARY INFORMATION: Subject to the restrictions on the cover page. Page: 7 / 9 

Picture 2 - Description of the required inspection area 

Picture 3 - Dimensions to be checked (R1, R2 and ‘diam_A’)

Pay extra attention in the areas marked 

below at radius transition of the slot 

Surface Area ‘B’ 

(highlighted in red)

SB-2016-72-50-00-1/00
Alert Service Bulletin No./Rev.:

ISSUED REVISED GE Aviation Czech tel.:+420 251 041 111

Beranových 65 fax: +420 257 216 983

199 02 Praha 9 – Letňany

Czech Republic

tel.: +420 222 538 111

fax: +420 222 538 222

PAGE No. REVISION

01 21 2016 - - - 8 of 9 -

GE PROPRIETARY INFORMATION: Subject to the restrictions on the cover page. Page: 8 / 9 

Table 2 - PT Disc area ‘B’ inspection 2 acceptance criteria

Description

Power Turbine Disc 

Part Number

M601-3220.6 & .5

Surface imperfections / tooling marks Replace

Linear FPI indication Replace 

R1, R2 not equal to 1+/-0.2 mm Replace, quarantine, repair 

being developed

Diam_A not equal to 45+/- 0.2 mm Replace

2. ACCOMPLISHMENT INSTRUCTIONS

2.1. According to 1.6. & 1.12 

2.2. Record an accomplishment of this Alert Service Bulletin in the Engine Log Book, including the date and 

the name of the person who has accomplished the Alert Service Bulletin. 

2.3. Send the inspection report to the GEAC Design Organization in accordance with the Engine’s Reliability 

program. 

3. MATERIAL INFORMATION

Required material and tooling are listed in appendix B. 

4. APPENDICES

Appendix A – List of serial numbers called Engines 

Appendix B - Inspection instruction 

SB-2016-72-50-00-1/00
Alert Service Bulletin No./Rev.:

ISSUED REVISED GE Aviation Czech tel.:+420 251 041 111

Beranových 65 fax: +420 257 216 983

199 02 Praha 9 – Letňany

Czech Republic

tel.: +420 222 538 111

fax: +420 222 538 222

PAGE No. REVISION

01 21 2016 - - - 9 of 9 -

GE PROPRIETARY INFORMATION: Subject to the restrictions on the cover page. Page: 9 / 9 

APPENDIX A - List of serial numbers called Engines

Engine 

Type

Engine 

Serial 

Number

Estimated

equivalent*

CSO

For engine 

till required 

inspection

Compliance 

deadline

Engine 

Type

Engine 

Serial 

Number

Estimated 

equivalent*

CSO

For engine 

till required 

inspection

Compliance 

deadline

E11 922009 2 849

Jan-16

E 874025 2 210

Apr-16

E 894031 2 936 E 881012 2 214

D2 932002 2 977 E11 881020 2 244

D2 864005 3 583 E 881021 2 193

E 882035 2 240

E 872013 2 234

Feb-16

E 882046 2 155

E 913006 2 250 E 882049 2 211

D1 894019 2 737 E 883017 2 250

D1 833027 2 575 E 883025 2 211

D1 852052 2 620 E 883037 2 230

E 883065 2 240

E 903001 2 250

Mar-16

E 884029 2 151

D 874004 2 250 E 891022 2 250

D 874006 2 250 E 891033 2 240

D 912018 2 250 E 891042 2 210

E 894010 2 240

E 883061 2 029

Apr-16

E21 904022 1 948

E 901043 2 172 E 904032 2 138

Z 931002 2 211 E 911001 2 240

E11 833244 2 172 E 911031 1 774

D 842066 2 240 D 912006 2 176

E 862003 2 240 E 913009 2 138

E 864204 2 154 E 914004 2 240

E 871001 2 156 E 914017 2 240

E 871016 2 061 E 922003 2 240

E 873039 2 240 E 941014 2 165

E 873041 2 250

*equivalent cycles – see definition in engine log book

SB-2016-72-50-00-1/00
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 1

INSPECTION INSTRUCTION

CONTENT 

1 Before disassembly 2

2 Disassembly 3

3 Disassembly of exhaust system 28

4 Disassembly of PT disc balancing plugs 35

5 PT disk inspection: 40

6 Assembly of balancing plugs 44

7 Assembly of the exhaust system 56

8 Assembly 71

9 Verification of the engine function 93

10 MATERIAL INFORMATION 93
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 2

1. Before disassembly 

Measure the engine vibration on the wing, Power Turbine and GGT section in accordance with 

appropriate engine model Maintenance Manual, chp. 72.01.01 2. 
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 3

2. Disassembly 

2.1. Disassemble the bonnet and propeller from the engine 

2.2. Close the bleeding valve and seal the intake screen to the engine and exhaust bends (on aircrafts 

with short exhausts) or disassemble the exhaust bends at the flanges (aircrafts with long 

exhausts). 

2.3. Release from the engine (from the accessory gearbox and reduction gearbox) oil to prepared 

container. To do so, disassemble from the engine the electromagnetic signaler of chips (can be 

left suspended on a cable) and to its place, install the preparation for release of oil from the 

reduction gearbox– 903.7. On the accessory gearbox, remove the magnetic plug -572.9 and 

assemble preparation -9020.7. After release of oil from accessory gearbox, put back the 

magnetic plug and secure it. 

Close the bleeding 

valve.

Seal both exhausts bends. 

motoru

Seal the intake 

screen.

Release oil from the 

reduction gearbox using the 

-903.7 equipment.

Release oil from the 

accessory gearbox using 

-9020.7 equipment. After 

release, take out the 

preparation and reinstall 

here and secure with 

magnetic plug.

Flange for 

electromagnetic 

signaller of chips

Check tightness of the flange 

for magnetic plug before 

securing.
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 4

2.4. Disassemble the extinguishing installation around the reduction gearbox including the holders (if 

assembled). Cover all pipes and openings. 

2.5. Disconnect the operating rod of the propeller governor from the propeller governor and 

disconnect it from the reduction gearbox flange including the holder (according to the version).

Disassemble the installation 

including the holder from the 

fire detector.

Disassemble the 

installation from the 

front bulkhead and the 

extinguishing pipe. 

Disassemble the installation from 

the flange of the reduction 

gearbox including the holders on 

both sides. 2x2 pieces of M6 nuts.

After disconnecting the 

rod from the governor, 

disassemble it together

with holder from the 

reduction gearbox flange. 

2 pieces of M6 nuts.
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 5

2.6. Disassemble the pipe of the feathering pump (if assembled together with EHO, on the engine 

versions M601D the pipe is connected on the front bulkhead). Cover the pipe and openings.

Disconnect the 

electrical 

installation 

cable from the 

pipe.

Unlock and 

loosen cap nuts.

Disassemble the cap 

on the front bulkhead

Rear bulkhead

Front 

bulkhead
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 6

2.7. Disassemble the control device of the propeller governor. 

2.7.1. Unlock and loosen nut -7142.4, fixing the eye-bending shafts of kinetic link -703.9 

to the double-lever, remove the eye from the double-lever pin (pin on the shorter 

arm of the double-lever). 

2.7.2. Disconnect the control pipe from the holder on the exhaust set. Loosen both nuts 

on the outlet flange and disconnect the control case M601-731.4 from the flange. 

2.7.1

.

2.7.2

.

Pertinax 

insulation. Liner

Holder of the 

control bushing

Exhaust housing

holder is between 

the screw head 

and insulation.

Individual eyes of the rods 

with spherical bearings 

secure with wire to prevent 

their falling out and getting 

lost.
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 7

2.8. Disassemble the pipe to EHA -864.9 (if assembled together with EHA) from the screwing of the 

propeller governor and electrohydraulic actuator and slide electrical installation cable with the 

propeller heating collector under it (if heating is assembled, otherwise do not unlock or loosen). 

Put the pipe back but do not secure it.

2.9. Disassemble all the electric installation from the reduction gearbox (i.e. from the propeller 

governor, electromagnetic chip signaler, electrohydraulic actuator (if assembled) speed 

transmitter, fire detector (if assembled) and ELM cable (if assembled) including holders to the 

cable installation. On electrical installation, disassembled electromagnetic chip signaler, collector 

for propeller heating (if assembled) and fire detector (if assembled) can be left. 

Unlock and loosen 

the hollow screw.

Unlock and loosen the 

cap nut on the 

propeller governor.

From the pipe -864.9 

disassemble the electrical 

installation cables. Leave 

holders where they are.

Note: Prior to the disassembly of the electric installation holder and 

the fire detector cable from the main flange of the reduction gearbox, 

mark the screws which the holders were assembled to. Thus, the 

subsequent assembly will be easier.
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 8

2.10. Disassemble the front holder -848.6 of the electric installation on the top connection of the 

exhaust housing fixed with 3 screws. 

 

2.11. Disassemble the air sealing pipe -828.7 from the flange on the exhaust housing, the air sealing 

pipe of the PT labyrinth -861.9 from the bulkhead and from the air intake pipe -1408.7. Cover the 

pipes. 

Disassemble the front holder -848.6 

(electric installation). Disassemble three 

screws with self-locking nuts.

Disassemble the air 

sealing pipe -828.7 

from the flange on 

the exhaust housing

(2 screws with lock 

washers), from the 

bulkhead

(disassemble covers), 

from the air intake 

pipe and from the PT 

labyrinth air sealing

pipe (cap nut).
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 9

2.12. Remove the air sealing pipe -880.9 and its sealing from the exhaust housing flange. 

Remove the air 

sealing pipe -880.9 

including sealing 

from the exhaust 

housing flange.

Sealing

If the pipe cannot be removed using hands, an 

extreme solution is holding the flange over a cloth in 

pliers and carefully removing it. Under no 

circumstances the pipe can be levered under the 

flange.
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 10

2.13. Disassemble the pressure oil pipe to GT 839.6 from the pressure oil pipe -826.6 and pressure oil 

bushing -827.9. Cover screwing and the pipe. 

2.14. Disassemble the pressure oil pipe -826.6, cover the openings.

2.15. Disassemble the scavenge pipe from the reduction gearbox -827.6, cover the openings.

The pressure oil pipe -826.6 The scavenge pipe -827.6

Pull the pipes -826.6 

and -827.6 from the 

accessory gearbox.

Cover the openings.

Disassemble the holders 

from the divinding plane 

of the engine.

Disassemble the 

covers from the front 

bulkhead, dispose of 

the sealing and leave 

the rubber washer for 

subsequent 

disassembly.

2.13 

Disassemble 

the pressure 

oil pipe to 

GT -839.6.

For easier 

disassembly of 

the pipes squirt 

with lubricant.

Unlock the lock washers, 

loosen and disassemble the 

nuts on both pipes 4 pieces.
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 11

2.16. Disassemble the pressure oil bushing by loosening cap nut -3006.9 from the oil intake pipe 343.9. 

Push the cap nut -3006.9 along the pipe -343.9 to the exhaust housing. 

2.17. Disconnect the torquemeter pipe -840.6 from the pipe -841.6. Remove the covers, the sealing and 

the rubber insert from the front bulkhead. The pipe could be left connected to the reduction 

gearbox and exhaust housing, but to make the following halving of the engine easier, it is 

recommended to disassemble the pipe. Cover the openings. 

Hold the bushing with 

wrench against the 

cap nut -3006.9 and 

loosen it.

The pipe can be left 

assembled to the reduction 

gearbox and exhaust 

housing.

Disassemble covers, 

rubber insert and 

sealing from the 

bulkhead.

After disassembly of 

the bushing, push the 

cap nut into the 

exhaust housing.

After disassembly, check 

that the sealing ring 

remained on the bushing, 

or take it out from the 

pipe -343.9 to prevent its 

falling in the engine.

Pipe -841.6

Disconnect the pipe -840.6 

from the pipe -841.6.
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 12

2.18. If you decide to disassemble the pipe, unlock, loosen and screw out the screw of the holder on 

the exhaust case. Then unlock and screw out two screws connecting the pipe to the reduction 

gearbox flange. Then disassemble the pipe. Seal the pipes and openings. 

2.19. After disconnecting the torquemeter pipe from pipe -841.6 and sealing them, attach cover to the 

pipe -841.6 to prevent forgetting it during assembly. 

Disassemble the pipe 

from the engine, seal 

reduction gearbox and 

pipes -841.6 and -840.6.

Pipe -841.6

Fix the cover to pipe -841.6 to 

prevent forgetting it later.
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 13

2.20. Disassemble the scavenge oil bushing -8030.9 by loosening the cap nut on the oil drain pipe -

862.8 and the cap nut -3007.9 on the scavenge oil pipe -304.7. Push the cap nut -3007.9 into the 

exhaust housing.

2.21. Disassemble the screw of the drain pipe LN 6169 with sealing rings 10x14 CSN 02 9310 

connecting the drain pipe -806.7 to the flange on the exhaust housing.

Disassemble the screw of 

the drain pipe.

Cover the pipe after the 

screw removal.

Disassemble the drain oil bushing.

After bushing disassembly, 

cover the oil drain pipe and 

push the cap nut into the 

exhaust housing
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 14

2.22. Disassemble the thermocouple transmitters cables. Then disassemble the thermocouple set bus 

from the flange. Move the bus away from the engine similarly as in 2.9. 

2.23. Disassemble individual thermocouple transmitters. Mark the thermocouples or write down their 

correct location for assembly (M601E, M601F, M601T, GE H-series). Verify the function of 

thermocouple transmitters using multimeter. 

Move the cables away from the 

engine in front of the front bulkhead.

Cover the flanges after thermocouples 

with adhesive plaster.

Carefully take the 

thermocouples out of the 

engine.

Disassemble 

cables from 

thermocouples.

Mark the 

thermocouples 

for the 

reassembly. Then 

store them safely 

away from the 

engine.
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 15

2.24. Disassemble and remove screws and nuts connecting the flange of the exhaust housing with the 

flange of the centrifugal compressor housing that have various holders under nuts (all long 

screws). Leave the other screws. 

2.25. Remove self-locking nut with washer on the centring screw of the reduction gearbox and fourth 

screw with nut in the longitudinal parting flange of the exhaust system and insert the “reduction 

gearbox holder” (first part of preparation). 

Disassemble and take out 

screws and nuts from the 

exhaust housing flange and 

centrifugal compressor 

housing that have various 

holders under nuts (i.e. all 

long screws).

First part of engine 

halving preparation, 

“reduction gearbox

holder” fix under the selflocking nut and its 

washer on the centring 

screw and under fourth 

screw of the longitudinal 

parting flange.

“Reduction gearbox holder” (first part of preparation for engine halving.

Leave short screws 

with nuts.
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 16

2.26. Remove the centring screw with nut and then three screws with nuts from longitudinal parting 

flange counted from the centrifugal compressor flange (on top and bottom part at cross dividing 

plane) and assemble part of the exhaust system holder with centring needles (the other part of 

the engine halving preparation). According to the picture.

Slide centering needle of 

the other part of the 

preparation to the 

opening in cross parting 

flange and then assemble 

the preparation to the 

longitudinal parting 

flange.

Assemble the other part of the 

engine halving preparation 

using two technological screws 

and nuts that are part of it. 

Tighten the screws and nuts.

Between the preparation 

and flange, insert spacer 

that is part of the 

preparation

In the bottom, fix the 

preparation with 

centring needle the 

same as the top part. 

Do not tighten the 

screws and nuts here.

Top part

Bottom part
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 17

2.27. From the assembled mount, take one by one pins and replace them with technological pins that 

are part of the preparation. Before disassembly, cover the air inlet screen to the compressor (if 

haven’t done at the beginning of the disassembly) to prevent foreign objects falling in the 

compressor. 

Unlock cotter pin, 

disassemble and 

replace pins of the 

engine mount with 

technological pins 

of the preparation.

Third part of 

the preparation.

Easily tighten 

technological pins of the 

preparation so that the 

pin could be still moved.

Final look of the assembled 

third part of the preparation.

At other types of engine mount, assemble flanges 

that are part of the preparation and fix the third part 

of the engine halving preparation to them.
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 18

2.28. Assemble to the engine the supporting part of the engine halving preparation, and place it on the 

top hinge of the engine and to achieve the right preparation position, insert centring ring on it. 

Then insert big spacer on the supporting part. 

 

Big spacer

Centring ring

Supporting part of 

the preparation

Insert centring ring over the 

cutout to the opening on the 

preparation and turn it so 

that it locks on the 

preparation.

Insert regulation washer 

to the preparation.
APPENDIX B to ALERT SERVICE BULLETIN No. SB-2016-72-50-00-1

GE PROPRIETARY INFORMATION P a g e | 19

2.29. On the assembled supporting part of the preparation, assemble the bearing part. Then insert pin 

with spacer and secure with cotter pin.

After assembling the 

bearing part, insert pin 

with small spacer so that 

the openings for cotter 

pin were aligned.

Bearing part of the 

engine halving 

preparation

Secure the 

bearing part of 

the preparation 

with cotter pin.

Slide the bearing 

part of the 

preparation to the 

supporting one.

Pin

Small spacer
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2.30. Connect the third part of the preparation with the assembled bearing and supporting parts using 

screw with washer. After tightening the screw, set the bearing part of the preparation so that the 

bottom part of the preparation is vertically away from the place on the reductiojn gearbox as in 

the picture 345 mm. Execute petting with two adjusting screws on the third part of engine halving 

preparation. 

Connect the third part of the 

preparation with assembler 

supporting and bearing part 

using screw with washer.

345mm

.

Using adjusting 

screws, set the 

bearing part so 

that the bottom 

part is 345 mm 

away from the 

marked place on 

the reduction

gearbox.

Place for 

measuring 

vertical 

distance to the 

preparation.
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2.31. From the case of the halving preparation, take out the other part, “slider” and assemble it to 

operational state. Then slide it on the bearing part of the preparation and fix it to the first and 

second part of the preparation. Then set it so both holders are perpendicular to the longitudinal 

axis of the engine. 

“Rider” part of the preparation.

Assemble the “slider” to 

operational state and 

slide it on the bearing 

part of the engine 

halving preparation.

Set the preparation so 

that both holders are 

perpendicular to the 

longitudinal axis of the 

engine.

Fix the “slider” to the reduction gearbox holder 

and to the other part with centring needle of the 

engine halving preparation, connect to the 

reduction gearbox holder by second or third eye.
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2.32. After assembling the preparation pre-tighten the system using screw No. 1 by 15 mm (which 

means 330 mm) and set so that the back holder is free without extra tension. This holder is meant 

to catch the back part of the exhaust system all the way to putting out the whole exhaust system 

outside centring needles.

Place on the reduction gearbox

from which the distance of the pretightening is measured.

Back holder set 

so it is free 

without extra 

tension. This 

holder is meant

to catch the 

back part of the 

exhaust system

all the way to 

putting out the 

whole system.

Pre-tighten the system using 

screw No. 1 so that the bottom 

part of the bearing is 330 mm 

away from the place marked on 

the reduction gearbox.

Screw No. 2 Screw No. 1

Pre-tighten 

by 15 mm to 

330 mm.

330mm

In the front part, secure the 

preparation with stopper 

(screw) to prevent falling of 

the „slider“.
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2.33. Screw out the nuts on the remaining screws of the exhaust housing flange and centrifugal 

compressor housing flange by approx. 4 mm. To the openings, insert crosswise 6 leading needles. 

Check that there is no thermocouple or air sealing pipe -836.6 in the exhaust housing, check that 

the cap nut -3006.9 and 3007.9 are on the oil intake pipes -343.9 and oil discharge pipe -304.7 

inserted to the internal space of the exhaust housing not preventing pulling out. 

Execute complete check 

of the engine and make sure 

that no part will prevent 

pushing away of the exhaust

system from the centrifugal

compressor housing.

Around the 

perimeter insert 

leading pins to 

openings (6 pieces).

Check whether cap 

nuts are on oil pipes 

slided to the internal 

space of the exhaust

system.
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2.34. Loosen the exhaust system with 4 forcing-off screws M6 at connecting screws in the length of 

the loosened nuts. Keep checking alignment of flanges and mobility of the PT (danger of damage 

of the blades of the power (free) turbine!). 

Insert 

forcing-off 

screws M6 in 

six openings.

Conduct forcing off 

very slowly and 

carefully. The flanges 

must be aligned all 

the time. During 

forcing off keep 

checking mobility of 

the PT.

Check mobility of the Power

Turbine with hand inserted in 

the exhaust nozzle. If the 

turbine gets stuck, the exhaust

system must be returned to 

the original position where 

movement still occurred and 

then keep on forcing off.
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2.35. After loosening the exhaust system, screw out the nuts on the remaining screws and keep forcing 

off to the end of threading of the forced-off screws while checking PT freeness and discharge 

pipe -304.7 freeness.

2.36. With slight pull at exhaust bends, remove the exhaust system on the holder from the generator 

part before the stopper and stop. Disassemble forcing-of screws and leading pins.

Stopper on the bearing 

part of the exhaust 

system.

Disassemble forcing-off 

screws and leading pins

from the exhaust system.

Stop the “slider” 

with the exhaust

system of the 

engine at the end 

of the holder using 

screw on the front 

holder.
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2.37. Catch the preparation with a crane, tighten the crane wire, remove the stopper on the bearing 

part of the engine halving preparation, release the “slider” and carefully remove the exhaust 

system from the holder. Cover the exhaust systém and store it in a convenient place with 

convenient conditions.

2.38. Check that the power (free) turbine blades bandage is not damage. 

Fix the crane by the front holder. Remove the stopper from 

the holder and release the “slider”. Then, remove the whole 

exhaust system from the holder using the crane.

After removal of the engine exhaust 

system, check whether the power 

(free) turbine blading cover is not 

damaged or whether there are no 

cuts on the turbine.
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2.39. Remove the cotter pin from the bearing and supporting part of the engine halving preparation 

and move away the bearing part so it does not obstruct further assembly. 

2.40. Check that there is no spacer on the flange of the centrifugal compressor housing, that is 

inserted between the centrifugal compressor housing and the exhaust housing. 

2.41. Secure the GT guide vane ring flange with the centrifugal compressor housing flange using four 

screws M5x12 CSN 02103.14 (including nuts and washers). 

Remove the spacer from the 

flange. This spacer does not 

have to be on the engine.

Fix the washer to the exhaust

system with lashing wire so it 

will not be forgotten during 

engine reassembly.

Technologically connect the 

PT guide vane ring to the 

centrifugal compressor 

housing (at least 4 screws 

crosswise).
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3. Disassembly of exhaust system 

3.1. Unlock the lock washers 6,2 ONL 3288.2 on the reduction gearbox and exhaust system flange. 

Loosen and remove 34 nuts M6 ONL 3248 and M6 ČSN 02 1402.44 and washers -4063.4. Leave 

only 2 nuts on the sides of the reduction gearbox near the levelling marks. Remove all the 

brackets and holders. 

Tools: unlocking pin, wrenches 

3.2. Pose the exhaust system with the reduction gearbox on the top. 

M6 ONL 3248

-4063.4

M6 ČSN 02 1402.44

6,2 ONL 3288.2
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3.3. Prevent power turbine from rotating with tools 300-475-2024 and 300-557-0038.Loosen 8 nuts -

3041.5 using socket wrench 300-313-3007 and remove lock washers -3058.9. Keep the nuts on 

the plate 300-745-7007 according to their numbers. Remove tool 300-475-2024. Remove the 

power turbine using tools 100-477-1004 and 100-477-1008. 

Tools: Tools to prevent PT from rotating 300-475-2024 and 300-557-0038, socket wrench 300-

313-3007, plate for the nuts 300-745-7007, tools for power turbine removal 100-477-1004 a 100-

477-1008

-3041.5

-3041.5

-3058.9

300-557-0038/02

300-745-7007

300-475-2024
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3.4. Unlock 12 lock washers 5,2 ONL 3288 and loosen 12 screws LN 5153 connecting bracket -4512.5 

and labyrinth seal - 4016.5. Then use 3 of these screws as jackscrews to disassemble bracket -

4512.5 from labyrinth seal - 4016.5. 

Tools: unlocking pin, socket wrench

-4512.5

Disassembled 

screwsLN 5153 and 

lock washers 5,2 

ONL 3288.2

Holes for 

jackscrews
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3.5. Loosen the last 2 nuts on the reduction gearbox and exhaust system flange. Remove exhaust 

system -4.5 from support ring -457.7 and reduction gearbox -6.6 using tools 100-477-1004 and 

100-475-2055. 

Tools: wrenches, tools for exhaust system removal 100-477-1004 and 100-475-2005

100-477-1004

100-475-2055

-4.5

-6.6
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3.6. Remove insert -659.9 and O-ring LN 5096 from PT shaft using tool 300-475-2037. 

Tools: tool for insert removal 300-475-2037

-659.9

LN 5096

300-475-2037
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3.7. Remove bolt -6107.9 connecting PT shaft -4004.7 and quilt shaft -6172.5. Use tool 300-475-2022 

to prevent PT shaft from rotating. Then remove lock retaining ring -6100.9 and ring -6014.9. 

Tools: special wrench 300-313-9009,tool for PT shaft holding 300-475-2022

300-475-2022 300-313-9009

-6170.9

-6100.9

-6014.9
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3.8. Remove support cone with PT shaft -403.7 from countershaft casing -62.2 using 3 jackscrews 

300-475-2011. Force-off support cone carefully, equally around perimeter. When all the tubes are 

loose, remove the support cone. Pay attention to quilt shaft -6172.5. It may get stuck in the PT 

shaft and then fall down. Remove bearing ring with rollers from quilt shaft -6172.5. 

Tools: jackscrews 300-475-2011

-6172.5

Bearing ring with 

rollers
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4. Disassembly of PT disc balancing plugs 

Before balancing plugs drilling remove all PT blades. 

4.1. Clean the contact surfaces of the power turbine disc and jig 200-440-9067 by compressed air. 

Contact surface - Jig 200-440-9067 Contact surface – Power turbine disc 

4.2. Set jig 200-440-9067 on the drilling table and install the protective tubes on the guide pins of jig 

200-440-9067. Place the power turbine disc on the jig 200-440-9067 and remove protective 

tubes. 

Tools: jig 200-440-9067, protective tube (part from 200-440-9067) 

Power turbine disc 

Protective tubes 

 

4.3. Install center drill number 400-221-1023 into the drill chuck. Place the 1,5 mm Johanson gauge 

on the body of the disk, inside balancing flange (as per picture below). Touch the Johanson gauge 

with the drill and set up the drilling stoper on the drilling machine. After drill stopper is set up, 

remove the 1,5 mm Johanson gauge from the PT disk. 

Tools: center dril 400-221-1023, Johanson gauge 1,5 mm 

Jig 200-440-

9067 
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CAUTION: PAY PARTICULAR ATTENTION TO THE DRILL STOPPER SET UP. IMPROPER SET UP COULD 

RESULT IN PERMANENT DAMAGE TO THE CRITICAL PART, RESULTING IN THE PT DISK BEING 

SCRAPPED 

 

 Johanson gauge Power turbine disc Center drill Setting drilling stopper 

4.4. Place the drilling template on the PT disc and secure it with M6 nuts. Drill through the balancing 

plug with center drill 400-221-1023 to the depth determined by the drilling stopper (which was 

set in op 3). After drilling, remove center drill 400-221-1023 from drill chuck, disassemble the M6 

nuts and remove the drilling template. Remove all chips from PT and jig 200-440-9067 with 

compressed air. 

Tools: drill template (part from 200-440-9067), center dril 400-221-1023 

 Drill template Power turbine disc Center drill M6 nut (2 pieces) 
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4.5. Install the Ø3,25 mm drill into the the drill chuck. Place the 1,5 mm Johanson gauge on the body 

of the disk, inside balancing flange (as per picture below). Touch the Johanson gauge with the drill 

and set up the drilling stoper on the drilling machine. After drill stopper is set up, remove the 1,5 

mm Johanson gauge from the PT disk. 

Tools: drill Ø3,25 mm, Johanson gauge 1,5 mm 

 

 Drill Ø3,5 Johanson gauge Power turbine disc Setting drilling stopper

4.6. Place the drilling template on the PT disc and secure it with M6 nuts. Drill through the balancing 

plug with 3,25mm drill to the depth determined by the drilling stopper (which was set in op 5). 

After drilling, remove 3,25 mm drill from drill chuck, disassemble the M6 nuts and remove the 

drilling template. Remove all chips from PT disk and jig 200-440-9067 with compressed air. 

Tools: wrench=10

 Drill template Power turbine disc Nut M6 (2x pieces ) Drill Ø3,5 

 
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4.7. Insert protecting shim under the balancing plug. If the balancing plug is touching the disk body, 

the protecting shim is not required). Insert the Kraftwek 3057-03 tool into the hole drilled in op 6, 

unscrew and remove balancing plug. 

Tools: removing tool - Kraftwerk 3057-03, reamer holder, protecting shim (part from 200-440-9067) 

 

 Power turbine disc Protecting shim 

4.8. Put the protective shim below the balancing flange, and restore the balancing hole thread by 

using M5x0,5 4H5H thread drill placed in reamer holder. 

Tools: thread drill M5x0,5 4H5H, reamer holder, protective shim 

Reamer holder Thread dril Power turbine disc Protecting shim 

Kraftwerk 

3057-03

Reamer 

holder
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4.9. Check thread using M5x0,5 4H5H caliber and check surface under the balancing flange for any 

signs of damage. The damage is not permitted. Report any existing damage. 

Tools: Caliber M5x0,5 4H5H 

 Caliber Power turbine disc 
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5. PT disk inspection: 

Inspection 1 # PT Disc inspection Instruction of the area below balancing plugs: 

Note – All balancing plugs need to be removed prior to area ‘A’ inspection

Perform Inspection of area ‘A’ (see Picture 1 below):

1. Visual Inspection – perform visual inspection under the good lighting (min 1000 LUX) with the 

magnifying glass (5x magnification) of the disk body - area ‘A’ (see picture below) according to the 

criteria listed in table 1. Pay particular attention to the areas below balancing holes. 

2. FPI Inspection – perform the FPI inspection of the disk body (per GEAC instruction P34.39) - 

area ‘A’ (see Picture 1 below) according to the criteria listed in the table 1. Pay extra attention to 

the areas below balancing holes. 

Picture 1 – Description of the required inspection area 

Table 1 - PT Disc area ‘A’ inspection 1 acceptance criteria

Description

Power Turbine Disc Part Number

M601-3220.6 M601-3220.5

Witness mark with no 

perceptible depth

Replace, quarantine, repair 

being developed Accept as is

Dot indication

If not deeper than 0.05mm and 

diameter less than 0.1mm

Replace, quarantine, repair 

being developed Accept as is

False drilled dimple

If depth is between 0.05mm to 

0.08mm and diameter more than 

0.1mm

Replace, quarantine, repair 

being developed

Replace, quarantine, 

repair being 

developed

False drilled dimple

Depth is more than 0.08mm

Replace Replace

Linear FPI indication Replace Replace

Pay extra attention in the areas 

below the balancing holes 

Surface Area ‘A’ 

(highlighted in red)
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Inspection 2 # PT Disc inspection Instruction of the PT disc slot area: 

Note – All balancing plugs need to be removed prior to area ‘B’ inspection

Perform Inspection of area ‘B’ (see Picture 2 below):

1) Visual Inspection – perform visual inspection under the good lighting (min 1000 LUX) with the 

magnifying glass (5x magnification) of the disk slot - area ‘B’ (see picture 2 below) according 

to the criteria listed in table 2. Pay particular attention to the areas at radius transition of the 

slot. 

2) Dimensional Inspection – perform dimensional inspection of the disk slot radii (R1 and R2) and 

slot diameter ‘diam_A’ (see picture 3 below) located in area ‘B’ (see picture 2 below) according 

to the criteria listed in table 2. Dimensional inspection of the R1, R2 and ‘diam_A’ to be 

performed at 4 equally spaced places around the slot circumference (measurement to be 

taken every 90 deg) 

3) FPI Inspection – perform the FPI inspection of the disk slot (per GEAC instruction P34.39) - area 

‘B’ (see picture 2 below) according to the criteria listed in table 2. Pay extra attention to the 

areas at radius transition of the slot 
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Picture 2 - Description of the required inspection area 

Picture 3 - Dimensions to be checked (R1, R2 and ‘diam_A’)

Pay extra attention in the areas marked 

below at radius transition of the slot 

Surface Area ‘B’ 

(highlighted in red)
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Table 2 - PT Disc area ‘B’ inspection 2 acceptance criteria

Description

Power Turbine Disc 

Part Number

M601-3220.6 & .5

Surface imperfections / tooling marks Replace

Linear FPI indication Replace 

R1, R2 not equal to 1+/-0.2 mm Replace, quarantine, repair 

being developed

Diam_A not equal to 45+/- 0.2 mm Replace
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6. Assembly of balancing plugs 

6.1. Balance according instruction M601-P10-31B. Fix PT rotor with blades in the balancing machine. 

Fasten thong and lock. 

Tooling: balancing machine

6.2. Oil the bearings. 

Tooling: balancing machine, oil

6.3. Plug in balancing machine to the computer. Choose button SYSTEM  SYSTEM DATA 

KONFIGURATION  GO TO. Choose PEDESTALS RIGHT SIDE. 

Tooling: balancing machine

Fixation points

Oil the bearings
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6.4. Check if computer cable is pluged in the balancing machine. 

Tooling: balancing machine
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6.5. Set-up balancing machine program for balancing rotor PT with blades. Choose ROTOR DATA 

READJUSTMENT  PT DISK WITH BLADES. 

Tooling: balancing machine
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6.6. Power on the balancing machine usage power on button. 

Tooling: balancing machine

6.7. Keep rotation in range of green value as below. 

Tooling: balancing machine

Power on
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6.8. As soon as both surfaces are balanced (see indication location below), press HOLD button. 

Tooling: balancing machine

6.9. Fill in initial inbalance mass status into assembly list. CAUTION! Surfaces in assembly list are 

rotated relatively to the display. 

Tooling: balancing machine 
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6.10. Press CORR. Display indicate ideal location of balancing plugs in both surfaces. At first balance 

the surface with higher inbalance mass. Choose balancing plug weight according table. For I. 

Surface use balancing plugs -3029.3 E, -3029.4 a -3032.4. For II. surface use -3029.3 B – D a -

3029.3 E – F. 

Tooling: balancing machine
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6.11. Fix PT rotor with blades in the stand. 

Tooling: Stand

6.12. Fix outer bearing ring and cage of rollerbearing N1007 with ball bearing QJ206 usage rubber 

band, so the bearing can ́t be damaged during balancing plugs locking. 

Tooling: rubber band

6.13. Screw up balancing plugs on PT disk. 

Tooling: screwdriver

Bearing N1007
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-3029.3 B, D, E, F

Screwdriver
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6.14. Lock balancing plugs on PT disk usage locking thorn. Balancing plug can ́t be released anymore. 

Tooling: locking thorn
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6.15. Screw up balancing plugs usage screwdriver. Long balancing plugs screw up on end stop, short 

ones have to be align with PT disk surface. Screwdriver grooves should point into the center of 

the disk. 

Tooling: screwdriver

6.16. Lock balancing plugs on PT disk usage locking thorn and hammer. Balancing plug can ́t be 

released. 

Tooling: locking thorn

6.17. White down in assembly list diagram assembled balancing plugs. Mark sawed-off balancing plug 

with X. Write down inbalance mass. Maximum inbalance mass according M601-P10-31B. 

-3029.3 E + H, -

3029.4 or -3032.4

Locking thorn
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Balancing plugs location 

Inbalance mass
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7. Assembly of the exhaust system 

7.1. Put ring of the roller bearing on the quilt shaft -6172.5. For easier assembly it is possible to “stick“ 

rollers to the quilt shaft with Vaseline. Put the quilt shaft -6172.5 into the countershaft casing -

62.2. Marked teeth of the quilt shaft must fit to the marked teeth on countershaft gears. 

Tools: 

-6172.5
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-6172.5

-63.6

-62.2

-6172.5
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7.2. Degrease contact surface of the support cone with PT shaft, complete -403.7 and contact surface 

of countershaft casing -62.2. Then apply Alhyl on those surfaces. Apply Vaseline on all the tubes 

and O-rings. 

Tools: Vaseline, Alhyl 

Degrease + apply 

Alhyl

vaseline

Degrease + apply Alhyl
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7.3. Put support cone with PT shaft complete -403.7, on the reduction gearbox -6.6. Mark on PT shaft -

4004.7 must fit between marked teeth of quilt shaft -6172.5. 

Marks on the PT 

shaft

Marks on the 

quilt shaft

-6172.5

-457.7

-4004.7

-6.6
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7.4. Put ring -6014.9, retaining ring -6100.9 and bolt -6170.9 into the PT shaft. Teeth on the lower side 

of the retaining ring must be rotated with 90° to the cut on the quilt shaft. Apply Molycote on the 

bolt -6170.9. 

Tools: Molycote 

-6172.5

Cut on the 

quilt shaft

-6170.9

-6100.9

-6014.9
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7.5. Put tool 300-475-2022 to bolt -6170.9. Cuts on the end of the tool must be rotated with 90° to the 

cuts on retaining ring -6100.9. Tighten the bolt. First tighten the bolt unless all the parts are 

moving. Then slightly release, rotate with the rotating part of the tool, meanwhile tighten and 

release until it is obvious that the teeth are in the cuts. Hold the PT shaft with the tool to prevent 

its rotation. Tightening torque is 25±2 Nm. Because it is not possible to see if the teeth are in the 

cuts, make sure, that these parts were assembled properly. In other case repeat this section. 

Tools: tool 300-475-2022, torque wrench 

-6170.9 -6100.9 otočná část 300-475-2022

300-475-2022
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7.6. Lock retaining ring -6100.9 with tool 300-476-0018. 

Tools: tool 300-476-0018/01, hammer 

D

D view

300-476-0018/01
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7.7. Put O-ring LN 5096 on insert -659.9. Put insert -659.9 into PT shaft -4004.7. Apply Vaseline on the 

O-ring. Side with the O-ring goes first. Hit the insert with tool Z3-01197-00 and hammer. Clean 

the contact surface of PT shaft. 

Tools: hammer, Vaseline, tool Z3-01197-00

-659.9

LN 5096

Z3-01197-00
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7.8. Check clearance V6/104 (0,25÷1,2) mm. Calculate it from the distance of the PT shaft contact 

surface and the surface of the insert. If the clearance is bigger, change the insert to meet proper 

values. 

Tools: depth gauge 

7.9. Put exhaust system -4.5 on support cone -457.7 and reduction gearbox -6.6. Place the exhaust 

system with the sign “xxx” to the levelling mark. Apply Konkor 101 on bolts -4053.4, -4065.4 and -

4066.4. Tighten at least 4 nuts on the reduction gearbox -6.6 and exhaust system -4.5 flange. 

Tools: Konkor 101, spanner 

7.10. Clean and degrease all contact surfaces of PT disc with blades. Cool PT disc to -18°C for 30 min. 

Clean and degrease all contact surfaces of bracket -4512.5. 

-4.5

-6.6

levelling mark

center screw
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7.11. Put bracket -4512.5 on labyrinth seal - 4016.5. Make sure that sign “xxx” is on the top of the 

engine. Apply Molycote into 12 holes of bracket -4512.5 and also on threads on 12 screws LN 

5153. Assemble screws LN 5153 and lock washers 5,2 ONL 3288.2. Tightening torque is (4÷5) Nm.

Then lock washers 5,2 ONL 3288.2. 

Tools: torque wrench, Molycote, locking pliers 300-312-2006

12x apply Molycote

5,2 ONL 3288.2

LN 5153

Sign of the top „xxx“

-4512.5
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7.12. Warm up the center and the flange of PT shaft to the 80°C temperature using warming tool or 

warming pistol. Apply Molycote on the line between two diameters on the PT disc. Traces of 

Molycote are not allowed on contact surface. Press power turbine into the PT shaft using tool Z3-

01197-00 and a hammer. The sign “xxx” must be on the top.

Tools: Molycote, hammer, tool for turbine pressing, warming tool 

Warming tool

Z3-01197-00
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7.13. Put nuts -3041.5 and lock washers -3058.9 on screws -3363.5. Firstly put the nut nr. 1 which is 

placed on the top (sign “xxx”). Other nuts put counter-clockwise. Before assembly apply Molycote 

on threads and contact surfaces of the nuts. Tighten crosswise. Tightening torque is 8 Nm. Then 

let settle down temperature difference. 

Tools: Molycote, torque wrench, plate for the nuts 300-745-7007

-3058.9

-3041.5

300-745-7007

-3041.5

-3058.9
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7.14. Install tool for measurement of elongation of the screws. Prevent the turbine against rotating 

using fixing tool. Put the tip of the indicator on the end of the screw and chceck elongation 

values. Tighten the nuts twice to the 0,105 ÷ 0,110 elongation of the screws. Check if the screws 

shrink back. Final elongation must be 0,075 ÷ 0,080. Tighten crosswise. Tightening torque must 

be within (5 ÷ 15) Nm. 

Tools: tool 300-557-0038/02, screwdriver, socket wrench 300-313-7030,tool for turbine stabilizing 

300-475-2024

300-557-0038/02

300-475-2024
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7.15. After tightening the screws lock the washers with locking pliers. Then clean and degrease all the 

surfaces 

Tools: locking pliers 300-312-5005

300-557-0038/02

300-313-7030

300-312-5005
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7.16. Attach all the brackets and holders you removed during the exhaust system disassembly.on the 

flange of the reduction gearbox and exhaust system. Tighten all the nuts M6 ONL 3248 with 

washers -4063.4 and nuts M6 ČSN 02 1402.44 with lock washers 6,2 ONL 3288.2. Tightening 

torque is 4+2 Nm. Then lock the washers. 

Tools: wrench, locking pliers 300-312-2006, torque wrench 

M6 ONL 3248

-4063.4

M6 ČSN 02 1402.44

6,2 ONL 3288.2
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8. Assembly 

8.1. Bind lashing wire to cap nuts of the oil pressure pipes -342.9 and oil drain pipes -304.6, i.e. cap 

nuts -3006.9 and -3007.9 for following pulling the nuts from the exhaust housing so that it has at 

least 250 mm. At M601D also bind the lashing wire to the bushing from the thermocouples. 

8.2. Disassemble the sealing from the lateral flange and one exhaust nozzle. Clean the contact 

surfaces of the flanges from the exhaust system of the engine. Check placing of the piston ring 

(position of the lock is arbitrary) by pulling a piece of paper under the piston ring. The paper will 

show the clearance between the ring and its flange. Cut overlapping paper with a razorblade. 

Bind lashing wire to 

the cap nuts (or 

thermocouple 

bushing). Due to the 

wire, you will be able

to pull the nuts 

through the exhaust 

housing, after 

connecting the 

exhaust system to

the generator.

Correct placing of the piston ring is achieved 

by inserting the piece of paper under the 

piston ring. Subsequently cut the paper.
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8.3. Attach the front holder of the engine halving preparation connected to the exhaust systém to the 

crane and slide it carefully on the bearing part of the engine halving preparation fixed on the 

aircraft. After that, stop the “slider” and insert a stopper to the end of the bearing part of the 

preparation before loosening the crane. Then remove the crane hook. 

Stop the “slider” 

with the exhaust

system on the 

holder using screw.

Insert stopper on 

the bearing part 

of the exhaust

system.

Fix the crane 

using the front 

holder.

After mounting the 

exhaust system of the 

engine to the bearing part 

of the engine halving 

preparation, disconnect 

the crane and prepare 

leading needles (6 pieces 

around the perimeter).

Stopper
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8.4. Disassemble technological screws from the GT guide vane ring flange and centrifugal 

compressor case flange and release the “rider” and move the outtake system so that it is possible 

to pull through lashing wires connected to cap nuts -3006.9 and -3007.9 through the exhaust 

case coat in the appropriate places (at M601D, pull the wire through from the thermocouple 

bushing). Then slide the outtake system to the position where the centring needles touch the 

front of the PT guide vane ring flange. In this position, check and adjust, if necessary, evenness of 

flanges, insert around the perimeter in the openings other six leading needles, then mount 

centring needles in the relevant openings in flanges of the PT guide vane ring and the centrifugal 

compressor case. Slide the outtake system even further so that the space between the flanges is 

20 mm in maximum, in this position, check again alignment of flanges, if necessary, set with 

screw No. 1 on the preparation. Screw No. 2 must be free, during approximation keep checking 

with your hand the mobility of the power (free) turbine. After securing the correct position, lightly 

move the outtake system to the PT guide vane ring flange and secure it with at least 6 screws 

with applied Molyka. Cap nuts of oil pipes -3006.9 and -3007.9 pull through the coat of the 

exhaust case. CAREFUL: do not forget to insert the washer between the exhaust case and flange 

of the PT guide vane ring if it was part of the engine. Check evenness even from the side (not only 

height-se), if necessary, press the coat of the outtake system to the relevant side. 

If washer was part of the engine, 

it must be reassembled. Check mobility of the 

PT turbine with your 

hand inserted in the 

exhaust. If the turbine 

gets stuck, the system 

must be returned to 

the position where it 

moved, and then 

continue in bearing 

on, or adjust the 

position.

Pull the cap nuts wires through 

the relevant openings.

Conduct bearing on very 

slowly and carefully. The 

flanges must be 

completely even all the 

time. Keep checking the 

mobility of the PT 

turbine.

Make sure 

the nut 

does not 

prevent 

sliding.
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8.5. Add number of other screws to the flange (in particular short ones, do not forget to rub them in 

Molyka) and disassemble the engine halving preparation from the engine. This includes the 

“rider”, the bearing and supporting part of the preparation and also the reduction gearbox holder, 

the other part with centering needles and the third part (while disassembling the third part, 

replace the pins of the preparation with pins of the engine bed progressively, the engine bed 

needles with crown secure with cotter pin.) Add screws and nuts to the longitudinal parting flange 

of the exhaust case at the openings from disassembled parts of the preparation. 

Disassemble all parts of the 

enging halving preparation and 

store them in the case.

Disassemble the second 

part of the preparation 

with centring needles 

from the top and bottom 

part.
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8.6. Connect the flanges of the centrifugal compressor case and the outtake system using 41 screws 

-3007.7, 19 screws -8019.7 (rub them in Molyka) and 60 self-locking nuts -3009.4 (numbers of 

long and short screws may differ, long screws are where a holder is connected under the nut). In 

the 10th opening (counted from the top connection of the outtake system clockwise, “in the 

direction of the flight”) insert screw -8019.7 and under the screw Ø 5.3 also holder -8015.6 

(slightly turned to the top of the engine). Insert holders of the front partition under the nut of 5th, 

15th and 25th screw, also insert and use screws -8019.7. At positions 11 and 12, insert the holder 

of the fire detector under the nuts (if assembled). 

To openings 2, 8, 14, 20 and 26 (right half of the engine), also insert screws -8019.7, connect the 

holders of the thermocouple collector under the nuts on these screws. 

To openings 3, 4, 6, 7, 8, 16, and 26 (counted from the bottom connection of the outtake system 

clockwise) insert -8019.7. Under the nuts of screws 3 and 4, insert the top part of the holder -

839.8, at screw 6 and 7, insert the top part of the holder -840.8 under the nut. Under the nut of 

screw 5, 15 and 25, insert the holders of the front firewall -8044.6. Under nuts 9, 16 and 26, 

connect the thermocouple collectors. On position 25 and 26, insert the holder of fire detector (if 

assembled). 

Tighten the nuts crosswise to 6 Nm. 

Screws with nuts under 

which the thermocouple 

collectors are connected.

Screws with nuts under 

which the holders of 

the front firewall are 

connected.

Screws with nuts under 

which the fire detector 

holder are connected.

Screws with nuts under 

which the top parts of 

the holders -839.8 and 

-840.8 are connected –

assemble by oil pipes.

Screw with nut under 

which the holder -

8015.6 is connected.

L P

2. 8.

.

14.

20.

26.

9.

.

16.

26.
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8.7. Measure individual thermocouples and check their state. (no clearance, nut must be tightened). 

8.8. To nine flanges on the exhaust case progressively insert 9 thermocouple transmitters (does not 

apply to M601D). Each thermocouple must go to the same place from which it was removed, their 

position is marked according to 1.22. Before tightening check whether each transmitter sits well 

in the flange, then tighten it with 2 screws LN 5135 (rub the screw screwing in the mixture of 

molybdenum sulphide and oil), insert lock washers 5.2 ONL 3288.2 under the screw heads, secure 

the screws after tightening. After assembly, check each thermocouple transmitter for damage on 

the electrical circuit with 4.5V ohmmeter. Test the thermocouple transmitters with “A” pole 

towards the reduction gearbox. 

8.9. Connect to the exhaust case flange thermocouple transmitter bus. According to the sketch on 

sheet 63. Before the bus platform is fixed, according to the need, release its inconvenient 

distortion with hand so that individual wires to be tightened and connected to individual poles of 

the thermocouple transmitters are not under extreme pressure, distorted, crossed, slacking, etc. 

To the flanges on the exhaust 

case, insert 9 thermocouple 

transmitters. Before 

tightening, try to centre the 

thermocouple transmitters.

Thermocouple 

transmitters position 

with “A” pole facing the 

reduction gearbox. 

After tightening of the 

screws, secure the lock 

washers.
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8.10. Assemble cables to the thermocouple transmitters. Connect cables with read heads to „Ch“ pole 

and the ones with green heads to „A“ pole. To connect the green head, use the LN 5444 screw 

and LN 5168 self-locking nut. To connect the read head, use the LN 5084 screw and the LN 5167 

self-locking nut. Position the cable heads to be almost horizontal with the exhaust case and to be 

oriented anti-clockwise (viewing from the direction of flight). The only exception is the connection 

of two thermocouple transmitters, where in one case, the cable heads are oriented to the front 

partition (at the thermocouple transmitter located next to the flange for intake of cooling air of 

the GT oil collector cover) and in the other thermocouple transmitter, the cables are oriented 

clockwise (the lowest thermocouple transmitter on the left side of the exhaust case). While 

connecting the wires to the thermocouple transmitter poles, make sure the wires are not torn, 

partially broken, crossed (i.e. damaged) and that the outlet thermocouple contacts are not 

damaged – bent – during assembly. During tightening, hold the screws, then secure them and 

place the wire eyes under the screw heads. After assembly, check insulation resistance of the 

whole thermocouple set with MEGMET 100 Vss device – the insulation resistance must amount to 

at least 5Ω. The rubber inserts of the holder can be put together from two parts, in certain 

strongly bandaged places of the platform, holder insert cannot be used. During assembly of the 

cable platform, maintain the distance of the cable outlets from the pipes (at least 5mm), at the 

platform, contact of braid and pipes is allowed. The screws are inserted to the thermocouple 

transmitters poles from the accessory gearbox, at the transmitter on the left side, they are 

inserted from top to bottom, and at the transmitter thermocouples (the bottom one on the left), 

they are inserted from the reduction gearbox. 

On the left side of the 

engine, there are two 

thermocouple transmitters 

– exceptionally positioned 

this way.
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8.11. At the exhaust case opening (pressure oil intake), take out the oil pipe cap nut using the lashing 

wire (or hook) through the sealing connection. Using the cap nut on the oil intake pipe, connect 

the pressure oil bushing -829.9, the bushing must be oriented for subsequent connection of the 

pressure oil pipe to GT. Insert sealing ring Js 4 -8056.9 to the ONL connections. Glue the ring to 

the bushing using vaseline, assemble the bushing and then remove it and check that the ring did 

not move. 

8.12. At the opening in the exhaust case (oil discharge), take out the oil pipe cap nut using lashing wire 

(or hook) through the sealing connection. Using cap nut, connect the pressure oil bushing -8030.9 

to the oil discharge pipe. Using cap nut, assemble the bushing to the oil discharge pipe and 

secure the cap nut. Insert sealing ring Js 8 -8058.9 to ONL connections. 

Insert sealing rings to ONL connections. 

CAREFUL: you must be absolutely sure that the 

ring did not move and does not prevent oil flow 

or cause pipe leakage.

Connect bushing using 

cap nut.

Insert sealing rings to ONL 

connections. CAREFUL: you must be 

absolutely sure that the ring did not 

move and does not prevent oil flow or 

cause pipe leakage.

Connect the 

bushing using cap 

nut with discharge 

pipe and secure 

both.

Connect the bushing using cap nut.

Apply 

Molyka to 

the bushing 

threading.

Apply 

Molyka to 

the bushing 

threading.
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8.13. To the hollow screw of the drain pipe LN 6169, insert sealing ring (Cu) 10x14 CSN 02 9310 and 

slide it through the discharge pipe -806.7, then mount another sealing ring on the screw and 

screw it to the flange threading on the bottom of the exhaust case. Secure the screw with lashing 

wire. Before assembly, apply Molyka to the hollow nut threading. 

8.14. Slide cover -8048.8 on the torqumeter pipe -840.9. Connect the torquemeter pipe to the pipe -

841.6 using cap nut. Tighten the nut and secure with lashing wire. Then mount the sealing -

8060.8 (2 pieces) and rubber insert -8061.8 to the pipe. Fix the sealing and rubber insert to the 

front firewall using covers -8048.8, fix the covers to the firewall with 2 screws LN 5084, washers 

LN 5156 and nuts LN 5167. 

Before assembly, place 

-8048.8 cover, -8060.8 

sealing and rubber 

insert -8061.8 on the 

pipe.

After connecting the pipe, 

tighten both covers on the 

front firewall.

Secure cap nut after 

tightening with 

lashing wire.

Insert hollow screw through 

the drain pipe and fix it to the 

exhaust case threading. On 

both sides of the pipe (on the 

screw), sealing rings (Cu) must 

be placed. After tightening, 

secure the screw with lashing 

wire.

Sealing rings (Cu) 10x14 CSN 02 9310
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8.15. Check O rings LN 5161 (2ks) and LN 5162 (2ks), which are on pipes -826.6 a -827.6, or replace if 

necessary. 

8.16. At the pressure oil pipe -826.6, clean the contact surfaces (on the side of the pipe to face the 

reduction gearbox) and apply a thin layer of Hylomar. Apply vaseline to the other end with the O 

ring. Then, insert the pipe to the cover -8048.8 and put pipes through the opening in the fornt 

firewall and insert the second cover. Insert one end to the accessory gearbox and the other to 

reduction gearbox. Insert sealing -8052.8 on pipe -826.6, insert cover -8053.8, sealing -8052.8 

and fix the covers to the partition with screws LN 5084, nuts LN 5167 and washers LN 5165. 

8.17. To the reduction gearbox, fix a pipe with two M5 CSN 021401.44 nuts, insert lock washers 5.2 

LMN 3290 under the nuts. 

8.18. Insert a washer on pipe -826.6 and fix the pipe to the flange of the exhaust case and centrifugal 

compressor case. Fix the bottom part of the holder -840.8 to the pipe and both parts of the holder 

with inserted rubber washer connect with 2 screws LN 5178 and self-locking nuts LN 5168. 

8.19. Assemble the pressure oil pipe to GT -839.6 using cap nuts to the pipe -826.6 and pressure oil 

bushings -827.9 and secure with lashing wire. On both ends, insert sealing rings Js 4 -8056.9 to 

ONL connections. 

8.20. To the pipe sucking oil from the reduction gearbox -827.6, insert a cover -8054.6 and insert -

8055.6 and covers connect similarly as in 4.41. Insert one end to the driver box and the other to 

the reducer box. Before assembly, coat on the side the contact surface of the pipe flange in 

Hylomar, and apply a thin layer of vaseline to the other end with O ring. Fix the pipe to the 

reduction gearbox with two nuts MS CSN 02 1401.44, insert lock washers 5.2 LMN 3290 under the 

the nuts.

Apply a thin layer of vaseline 

on the end of pipes with the 

O ring and put them in the 

accessory gearbox.

Before pulling 

pipes through the front firewall, slide a cover on them, as well as 

after pulling, before storing the pipe in the accessory gearbox.
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8.21. Slide insert on the pipe -827.6 and fix the pipe to the holder on the flange of the exhaust case and 

to the centrifugal compressor case using the bottom part of the holder -839.8, screw LN 5190 

and nut LN 5168 (a rubber washer is inserted in the holder). Put sealing -827.6 on the pipe. 

Tighten the covers -8048.8 

-8049.8 with sealings and 

inserts on the front firewall.

According to 5.44, 

assemble the pipe 

-839.6 and secure. 

On both ends, insert 

to ONL conections 

sealing rings Js 4-

8056.9

Clean contact surfaces 

and apply thin layer of 

Hylomar (only the cap 

part).

Fix pipes to the 

flange of the 

exhaust case and 

centrifugal 

compressor case

with holders.

Between covers, 

insert sealing -8052.8 

(for pipe -826.6) or 

8054.9 (for -827.9) 

and rubber washers -

8053.8 (for -826.6) or 

8055.6 on the front 

firewall.
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8.22. In the flange of the exhaust case, insert air intake pipe -880.8. Apply ALHYL paste on the flange 

on the exhaust case before assembling the air pipe for sealing. 

Apply ALHYL paste to the 

contact surfaces from both 

sides.

Insert the pipe in the opening 

on the exhaust case. Make sure 

the pipe is in the right position. 

“XXX” marking must face the 

reduction gearbox.

Apply ALHYL paste to the 

exhaust case flange.
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8.23. To the inflate pipe -828.7, slide cover -8048.8 from the side with O ring, slide the pipe through the 

opening in the front firewall and slide on the other cover -8048.7. Apply thin layer of MOGUL LV 2-

3 vaseline to the side of the pipe with the O ring LN 5295 (or other tested vaseline, e.g. vacuum 

one) and insert it to the connection of the air outtake pipe -108.7 and secure them. Connect the 

other end of the pipe to the exhaust case flange using screws ONL 3282.2 and secure them. Seal 

all contact surfaces of the flange and sealing with ALHYL paste. Then assemble the inflate pipe -

828.7 with the labyrinth inflate pipe PT -861.9 using cap nut, and secure the nut with lashing wire 

after tightening. Then, insert, between sealing covers -8005.7, rubber insert -8006.7 and sealing -

8005.7 on the inflate pipe -828.7 and fix them in the opening in the front firewall with covers 

using LN 5084 nuts and LN 5167 nuts. Insert washers LN 5165 under the nuts. 

Slide the end of the 

pipe with O ring to 

the air discharge 

pipe. Apply thin layer 

of vaseline to the 

ring.

Apply ALHYL 

paste to the pipe 

contact surface.

After tightening the screws, 

secure lock washers. Then 

connect the PT labyrinth inflate 

pipe using cap nut, and secure 

the nut with lashing wire.

Insert sealing 

covered in ALHYL 

paste between 

the inflate pipe 

and the air 

intake pipe.

Between covers in the front firewall,

insert rubber sealing washer and 

tighten the cover screws.
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8.24. On the top part of the exhaust case, mount to 3 -4055.4 screws the front holder (cable platform) -

848.6 (screws to position 2, 11 20 from the reduction gearbox flange). 

Assemble the front holder -848.6 (cable platform) to three 

screws -4055.4 with relevant self-locking nuts -3009.4.
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8.25. Connect electrical installation and fire detector (if assembled) cables to the front holder -848.6 (to 

the cable platform). 

8.26. Loosen the pipe to EHO -846.9 (if assembled along with EHO) from the propeller governor and 

electrohydraulical actuator screwing and slide electrical installation cable with the propeller 

heating bus under it. Then reassemble the pipe, tighten and secure cap nut with lashing wire on 

the side of the propeller governor and hollow screw on the side of electrohydraulic actuator (at 

versions with propeller heating). 

Release the pipe to 

EHO, slide the propeller 

heating bus cable under 

it and reassemble the 

pipe. Tighten and 

secure with lashing 

wire the cap nut on the 

propeller governor side 

and the hollow screw 

on the electrohydraulic 

actuator side.

Connect cables to the front 

holder (cable platform) using 

three connectors.
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8.27. To the reduction gearbox flange, assemble, to position 3 and 4 to the left clockwise from the 

centering screw fire detector (if assembled) using two self-locking nuts M6 ONL 3248, and insert 

washers LN 5275 under them. Fix the cable with holder to the reduction gearbox flange to 

position 1. 

8.28. Lead the cable to the revolution indicator transmitter. At engines with EKO, lead it along it and fix 

it by holders and two longer screws (under two nuts M6 CSN 02 1402.44 with lock washers 6.2 

LMN 2390) of electrohydraulic actuator. At engines without EHO, fix the cable to the reduction 

gearbox flange on position 1 to the right next to the centring screw and to two screws (under 

nuts M6 CSN 02 1402.44 with lock washers 6.2 LMN 3290). Insert the plug to the revolution 

indicator transmitter, tighten and securing with lashing wire. Secure lock washers. 

Assemble fire detector including the holder to 

position 3 and 4 using two self-locking nuts M6 

and washers LN 5275.

Fix the detector cable to 

the reduction gearbox

flange to position 1.

Centring screw
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8.29. If electrohydraulic actuator is part of the engine, insert to it the relevant connector (plug), tighten 

and secure with lashing wire. 

8.30. Lead the electrical installation cable to the propeller governor and electromagnetic signaller of 

chips (or to the ELM switch). If EHO is part of the engine, lead the cable along the pipe to EHO -

864.9 (two holders). If EHO is not part of the engine, connect the cable to screw 9 on the reduction 

gearbox flange from the centring screw. Or assemble the cable according to the original 

assembly. 

Secure the connector with lashing 

wire from the drilled flange 

through cap nut to the connector 

screws.

Insert the connector to the 

electrohydraulic actuator.

Lead the cable along the pipe to 

EHO -864.9 to the propeller 

governor flange.
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8.31. Assemble the pipe of the feathering pump -818.6 (if it was assembled). On it, slide the cover sheet 

-8048.8, sealing -8058.8 and rubber insert -8059.8 and slide it through the front firewall. Then 

slide on the cover sheet from the other side and fix and tighten cap nuts on both sides of the pipe 

and secure with lashing wire. To make the subsequent assembly of electrical installation of the 

magnetic signaller and propeller governor easier, slide the relevant cables between the reduction 

gearbox case and the feathering pump pipe. 

Fix the feathering pump pipe -818.6 and secure with 

lashing wire. Before fixing the pipe, slide the 

electrical installation cable under it. Fix the cable to 

the pipe. 

Slide cover sheet -8048.8, sealing and rubber 

insert on it and slide it through the front firewall, 

then insert cover sheet from the other side. After 

fixing the pipe tighten the covers.

 Front firewall

 Rear firewall

Sealing (-8058.8)

Rubber insert (-8059.8)
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8.32. Connect the connector to the ELM switch and secure with lashing wire. If ELM is part of the 

engine. 

8.33. Assemble the control rod of the propeller governor to the reduction gearbox flange with holder 

and two nuts M6 CSN 02 1402.44 with lock washers 6.2 ONL 3288.1. Secure the nuts (if such kind 

of control is assembled).

Connect the 

connector to the 

ELM switch. Secure 

the connector with 

lashing wire.

Fix the cable to the 

propeller governor.

Assemble the control rod 

to the reduction gearbox 

flange using 2 M6 nuts 

with lock washers. Secure 

the nuts.
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8.34. Electrical installation cable attach to the feathering pump pipe -818.6, or as it was attached 

originally. Then connect, tighten and secure the plug to the propeller governor. Or connect and 

tighten plug ELM (if it is part of the engine). 

8.35. Fix the remaining cable to the filter screw -615.4 according to the picture and then connect and 

secure the electromagnetic signaller of chips.

Attach the cable to the feathering 

pump pipe (according to the 

version, if not already done 

pursuant to 4.57).

Connect plug to the propeller 

governor and secure it with 

lashing wire against loosening.

Connect the cable to the 

filter screw -615.4 (can 

be connected to the 

other screw).

Connect and secure

the electromagnetic 

signaller of chips.
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8.36. Disassemble propeller regulator control device. 

8.36.1. Connect the control case -731.4 to the holder on the outtake set using to LN 5289 screws. 

Fix the case so that the holder of the outtake box is under the screw heads, then there is 

insulation -7114.4, then case holder, insulation -7114.4 and -7036.7 liner. Tighten the 

screws using nuts M5 CSN 02 1401.44, insert lock washers 5.2 ONL 3288.2 under them 

(see scheme below). Apply thin layer of mixture of molybdenum sulphide and oil (Molyka) 

to the screw threading. Insert the holder from the torquemeter pipe under the bottom nut 

with lock washer (at M601E versions). 

8.36.2. Connect connecting eye-bending shafts of kinetic connection -703.9 to the double-lever

(double-lever pin) using crown nut -7142.4 and cotter pin LN 5009, and secure it. 

8.36.3. Connect control rod of the propeller regulator to the propeer regulator using pin, washer 

and cotter pin, and secure it. 

8.36.2

8.36.1

Between the 

screw head and 

insulation, 

exhaust case

holder is located.

Control case 

holder

Pertinax 

insulation

Liner

8.36.3
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8.37. Assemble the water extinguishing platform, secure the cap nuts with lashing wire (if assembled). 

8.38. Check the completeness of the engine. 

8.39. Assemble propeller and bonnet. 

8.40. Add oil to the engine, discharge air from the oil system. Record the executed work in the engine 

log book. 

8.41. Verification of the engine function execute with engine test according to the “Manual for 

technical operation”, part 72.03.00 (apart from points 7 and 11) including test flight. 

Assemble the platform 

to the front firewall and 

the extinguishing pipe 

using cap nuts. Secure 

the nuts with lashing 

wire.

Assemble the 

platform to the 

holder of the fire 

detector.

Assemble the platform to the 

flange of the reduction gearbox

using the holders on both sides. 

2x2 pieces of M6 nuts and lock 

washers 6.2 ONL 3290.
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9. Verification of the engine function 

 Execute verification of the engine function by the engine perfomance test and measure 

the Power Turbine and Gas Generator Turbine engine vibration on the wing, according to appropriate 

engine model Maintenance Manual, chp. 70.01.01 and compare with measurement in pharagrph 1. 

 Record the maximum and minimum values of spline wear for quill shaft and the PT shaft into the 

engine log book. 

10. MATERIAL INFORMATION 

10.1. Material Required 

Code Name Drawing No. Amount 

019-0-T074302 Lock washer 5.2 ONL 3288.2 150 pieces 

019-0-T055174 Screw – GT distributor M601-3632.7 A 2 pieces 

019-0-T055175 Screw – GT distributor M601-3632.7 B 2 pieces 

019-0-T055176 Screw – GT distributor M601-3632.7 C 2 pieces 

019-0-T055177 Screw – GT distributor M601-3632.7 D 2 pieces 

019-0-T055019 Safety – GT nut M601-3048.4 20 pieces 

019-0-T071594 Nut M6 – exhausts LN 5281 16 pieces 

019-0-T074303 Lock washer, exhausts 6.2 ONL 3288.2 25 pieces 

019-0-T072897 Screw LN 5135 25 pieces 

019-0-T074622 Sealing ring 10x14-copper CSN 02 9310.2 4 pieces 

019-0-T065439 Sealing ring, d4 Js-4 M601-8056.9 10 pieces 

019-0-T065441 Sealing ring, d8 Js-8 M601-8056.9 10 pieces 

019-0-T065440 Sealing ring, d6 Js-6 M601-8056.9 2 pieces 

019-0-T065052 Insert – oil pipe M601-8072.8 1 piece 

019-0-T065055 Insert – oil pipe M601-8073.8 1 piece 

019-0-T071517 Nut M5 LN 5250 45 pieces 

019-0-T071518 Nut M5 LN 5251 2 pieces 

019-0-T055042 Screw M 4x6 M601-3004.3 12 pieces 

019-0-T055183 Stud M601-3061.7 A-B 2 pieces 

019-0-T55184 Stud – lab long M601-3061.7 A-B 2 pieces 

019-0-T55126 Stud – lab short M601-3061.7 A-B 1 piece 

019-0-T74360 Lock washer 4.2 LMN 3290 4 pieces 

019-0-T74361 Lock washer 5.2 LMN 3290 15 pieces 

019-0-T74362 Centering screw 6.2 LMN 3290 10 pieces 

019-0-T57005 Centering screw M601-4054.4 2 pieces 

019-0-T57016 Screw M601-4054.4P 2 pieces 

019-0-T57006 Washer – reducer M601-4055.4 4 pieces 

019-0-T75874 Nut M6 LN 5275 4 pieces 

019-0-T70064 Washer – roller CSN 02 1402.44 5 pieces 

019-0-T57007 Washer 14x18 – Al M601-4062.4 1 piece 

019-0-T74644 Safety – detector CSN 02 9310.3 1 piece 

019-0-T75878 Screw – air outtake LN 5333 8 pieces 

019-0-T72994 Stud LN 5410 4 pieces 

019-0-T54031 Stud M601-2004.44A 2 pieces 

019-0-T54032 Insulation (pertinax) M601-2004.4B 2 pieces 
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019-0-T64012 Sealing M601-7114.4 2 pieces 

019-0-T65425 Sealing M601-8005.7 2 pieces 

019-0-T65120 Sealing M601-8052.8 2 pieces 

019-0-T65122 Sealing M601-8058.8 4 pieces 

019-0-T65126 Sealing M601-8060.8 4 pieces 

019-0-T65128 Screw M4 – partition LN 5084 20 pieces 

019-0-T73012 Washer d4 LN 5165 20 pieces 

019-0-T75807 Self-locking nut M4 LN 5167 20 pieces 

019-0-T71576 Screw M5x22 LN 5289 2 pieces 

019-0-T73030 Self-locking nut M5 LN 5168 10 pieces 

019-0-T71577 Screw – pipes sleeve LN 5190 4 pieces 

019-0-T73020 Screw M 5x8 M601-3005.3 4 pieces 

019-0-0392099 Self-locking nut M5 M601-3009.4 40 pieces 

019-0-0898005 Sealing M601-3010.3 2 pieces 

019-0-0360535 Sealing M601-3012.3 2 pieces 

019-0-0360536 Sealing M601-1010.6 2 pieces 

019-0-0360620 O sealing ring – core LN 5120 2 pieces 

019-0-0899850 O sealing ring - core LN 5341 2 pieces 

019-0-0360727 O sealing ring LN 5096 2 pieces 

019-0-0360513 O sealing ring LN 5161 2 pieces 

019-0-0360641 O sealing ring LN 5162 2 pieces 

019-0-0360642 O sealing ring 13x2 LN 5272 1 piece 

019-0-0900261 O sealing ring M601-6147.4 1 piece 

019-0-0900277 Sealing ring LN 5299 1 piece 

019-0-0360673 Sealing ring – oil filter LN 5301 1 piece 

019-0-0360675 Sealing – intake pipe M601-8082.8 2 pieces 

019-0-0360599 Sealing – sheet M601-2534.5 6 pieces 

019-0-0360621 Screw M6 – exhausts M601-4556.6 16 pieces 

019-0-0898011 Screw – parting plane, short M601-3007.7 25 pieces 

019-0-0898014 Screw – parting plane, long M601-8019.7 10 pieces 

019-0-0909233 Self-locking nut M6 ONL 3248 4 pieces 

019-0-0401731 Countersunk screw shell M3x10 CSN 02 1151.22 4 pieces 

019-0-0411546 Control cotter pin LN 5209 10 pieces 

10.2. List of auxiliary material 

Name Code Amount 

Benzine 0116103

Acetone 0357298

Aero shell grease NR.6 0116459 

Molyka 0116601

Hylomar 

Varnish S2321/1000 

Brush 0965412

Loctite 243 0353232 

Technical patch 0975142

Wire KR 0,63 L-AKVS lashing 0226705

Wire KR 0,8 1CH18N9T lashing 0227031

Wire KR 05 42 3213.11 lashing 0289793

Alhyl paste 
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Steel brush 

Lapping paper 

Tent canvas 1m2 

Galloon white 5m 

Rubbers 6 pcs 

10.3. Tooling 

Disassembly

300-475-2024 přípravek proti otáčení PT

300-557-0038/02 přípravek proti otáčení PT + držák hodinek

300-745-7007 podložka na matice PT

100-477-1004 přípravek na demontáž kola PT

100-475-2055 přípravek na demontáž skříně výstupu

100-477-1008 přípravek na demontáž kola PT

300-475-2088 přípravek na demontáž vložky hřídele PT

300-475-2022 přípravek na přídržení hřídele PT

300-313-3027 

přípravek na demontáž šroubu 

z torz.

300-475-2012/01 odtlačovací šrouby 3x

300-476-0122 přípravek na demontáž torz. Hřídele

Assembly

300-346-3002 přípravek na montáž vložky hřídele PT

300-313-9009 přípravek na utažení šroubu torzní hřídele

300-476-0018/01 přípravek na zajištění šroubu TH

300-313-7030 klíč na matice PT

setinové hodinky 

hloubkoměr 

nástrčný klíč s-10

záslepka na regulátor vrtule